HelpTutorialsHow to Fix and Repair Your 3D Files Using Meshlab and Netfabb

How to Fix and Repair Your 3D Files Using Meshlab and Netfabb

Introduction

If you’ve run into an error while uploading your design file, don’t fret—because this tutorial is here to help! Shapeways recommends a few programs that you can use to check and prepare your file for 3D printing.

MESHLAB: Importing, Converting, and Exporting

MeshLab can open and export in several file formats that Netfabb cannot. If your file isn’t in the right format and your software doesn’t export in one of the format options that Shapeways can read, you can use MeshLab to convert it.

Shapeways requires that models be uploaded in DAE, OBJ, STL, X3D, X3DB, X3DV, or WRL for most 3D prints and for Full Color Sandstone, DAE, WRL, X3D, X3DB, or X3D is required. (For more information on exporting for full color materials, visit our Exporting for Color Printing Tutorial

Shapeways also requires that files be under 64mb in file size and have less than 1,000,000 polygon (triangle) faces. If your 3D file is larger than either of those parameters, you can use MeshLab for polygon reduction which will reduce your geometry’s number of faces and file size. You can learn more on how to reduce your polygon count in Meshlab, with our Polgyon Reduction with Meshlab Tutorial.

When you import a file that already has a UV texture map applied or has embedded color by face, it should automatically load in color.

If you do not have a texture map and are looking to create one, this process will depend on your 3D application. More information can be found in your respective 3D application website, or you can ask fellow designers in our community using our forums.

NETFABB: Measure, Check and Repair

This is a free program that can edit STL files. It can open an STL file and then shows basic failures on a model. The program also has basic STL file editing features such as analysing, scaling, measuring, and repairing.

Measure:

Not all 3D design software packages can scale a 3D design model “true to life.” For instance, you may design a ring sized to your finger in your design software but when you go to print it, you discover that your model file is resembles the size of a bowling ball.

Check:

Netfabb is a great tool for checking your model for productibility. Equipped with a more sophisticated measuring tool than Meshlab and model slicing tool, Netfabb can very accurately measure and analyze all the features of your model to make sure they are strong enough to be produced.

In 3D geometry, models are composed of 3 elements, vertices (points) edges (lines between points) and faces (surfaces between lines). In order for a 3D file to be printable, it needs to have “manifold” geometry. When a 3D file is manifold, then every edge is connected to only two faces. When Non-Manifold geometry is found in a model, 3D printers will have issues reading the file. To learn more about Non-Manifold Geometry and creating Water-Tight 3D files, check out our Things to Keep in Mind when Designing for 3D Printing Tutorial.

Repair:

Luckily the Netfabb Repair Tool can automatically fix most of these issues. When repairing in Netfabb, your model will be refined to have the following qualities:

Zero Holes: model will be manifold, without any gaps between faces and edges

Zero Border Edges: a border edge is an edge on the side of a hole, or the edge side of a plane if another edge is it's missing

Zero Invalid Orientations: In Netfabb, the direction of a face is shown in green if it points outward, red if it points inward. If you have red faces pointing out, that will be invalid orientation because it is inconsistent.

Positive Volume: All the green faces face out and the red face in, otherwise the printer will think that everything outside the model is material causing printer issues.

Closed Surfaces: A closed surface means that there are no holes or border edges.

Orientable Surface:All faces must be defined as in or out, with no stray edges or vertices.

To learn more about how to use Netfabb to scale, fix, and measure your model, check out this five-step tutorial.

If the automatic repair tool didn’t work to fix the errors in your model, it’s worth trying the functionality in the more powerful Netfabb Cloud Service. This online software is very similar to the professional, customized repairing that Shapeways runs on your model before printing.

A Note on Repairing: Although Netfabb’s Repair Tool is automatic, mistakes may still occur. Always check your model thoroughly afterwards to make sure it didn’t close any of the wrong holes or delete any important geometry.

Once you’ve converted your file to the right format and adjusted the scale and size to fit within the maximum size for your chosen print material, applied the texture as necessary, and checked that it meets all of the Design Guidelines and repaired it, you will be ready to upload your design and place an order.

You’ll be glad you gave your model the extra attention and care to make sure everything was perfect before printing, because the results will show!